This proposal requests continuation of support for Rand's P50 Population Research Center, extending over a five-year period. The requested program would support the continuation of 3 existing cores (Administrative Core, Data Core, and Research Dissemination Core) and a program of 11 research projects on the demography of families and households (one of the two original foci with which the Center began in 1979). Unifying our proposed research program are: 1. Two interrelated concerns with: (a) transitions by which families and households are formed and reshaped; and (b) the reciprocal influences of parents and children on each other; 2. A common conceptual framework combining economic, sociological, psychological, and demographic perspectives on family and household structure and change; 3. Coordinated use of several large longitudinal micro datasets whose complementarities enable us to test common sets of hypotheses; 4. Common approaches to methodological issues. This research program maintains continuities with our previous research while intensifying our focus on an area that has proven scientifically fruitful: the study of demographic facets of families and households, their influences on the behavior of individuals, and the economic and sociological theories by which that behavior can be explained. The program will continue to profit from three strengths of Rand's population studies: (1) our success in melding several disciplinary perspectives to advance our understanding of household and family behavior, (2) our use of large-scale, longitudinal datasets to conduct analyses at the individual and household levels, and (3) our application of demography to issues of public policy.